农林科学最新文献

Timely diagnosis is essential for managing feline panleukopenia (FPL), a devastating disease of cats caused by feline parvovirus (FPV) or canine parvovirus variants (CPV-2a, -2b, -2c). To support swift clinical decisions, point-of-care (PoC) antigen kits offer frontline tools. Given their cost and availability advantages, CPV-specific kits are often used off-label in cats; however, their interchangeability with manufacturer-matched FPV-specific kits remains unverified. This study assessed the diagnostic agreement between paired canine- and feline-specific PoC parvovirus antigen tests from two manufacturers. Fifty cats (30 with acute gastroenteritis, 20 healthy) were tested using all test formats. All cats underwent PCR and sequencing for parvovirus typing. Tests from the same manufacturer showed near-perfect or perfect agreement for result interpretation (Cohen's κ: 0.919 and 1.000). This strong inter-kit concordance also extended to test line intensity (κ = 0.908 and 1.000). Antigen-positive results were limited to diseased cats, mirroring the distribution of PCR positives. The latter included all the 30 cases, and were typed by sequencing as follows: 28 FPV, 1 CPV-2a, and 1 CPV-2c. All kit types detected FPV and CPV variants, and agreement within each manufacturer's paired kits was consistent across detected viral types. This preliminary evidence suggests that for two manufacturers, CPV antigen tests were non-inferior to their FPV counterparts, supporting flexible, cost-effective FPL diagnosis in cats, regardless of implicated parvovirus types.

Canine mammary tumor is the most common tumor in intact female dogs and poses a growing health burden due to its high malignancy rate and increasing canine populations. However, research on sarcomatous subtypes has been hindered by a lack of representative cell lines. Here, we successfully established a novel canine mammary liposarcoma cell line, designated CMLPS-N1, which represents the first such model derived from a spontaneous tumor. This cell line has been stably maintained for over 80 passages and exhibits an abnormal karyotype, high proliferative and migratory capacity, and strong tumorigenicity in mouse xenografts. Molecular profiling confirmed a phenotype consistent with liposarcoma (MDM2+) and mesenchymal origin (Vimentin+/N-cadherin+), alongside high-risk markers (p53+/Ki67+/Notch1), and hormone receptor expression (ER/PR), while being negative for epithelial (PCK) and HER-2 markers. We used functional assays, including cell proliferation, colony formation, wound healing, and transwell invasion, to confirm its aggressive phenotype. Furthermore, cytotoxicity testing with four chemotherapy agents further supports its utility as a preclinical model for therapeutic screening and mechanistic research. The establishment of CMLPS-N1 enriches the canine mammary tumor cell line repository and provides a valuable experimental model for studying disease mechanisms, developing therapies, and facilitating translational applications.

Cushing's syndrome (CS) is a common endocrine disorder in dogs that can significantly impair their quality of life. Diagnosis is often challenging because of its variable clinical presentation, making it difficult to identify suitable candidates for further diagnostic tests. This study employed machine learning algorithms to assist in CS diagnosis using routinely available screening diagnostics, including complete blood count, serum chemistry panel, and urinalysis parameters such as urine specific gravity and urine protein-to-creatinine ratio. Data were collected from 153 control dogs initially suspected of CS but later excluded and 152 dogs with confirmed CS. A boosted tree algorithm (gradient boosting) was trained on 80% of the collected data, with the remaining 20% reserved for testing. The developed model demonstrated an accuracy of 88.5% [95% confidence interval (CI): 80.5-96.5%], a sensitivity of 83.3% (95% CI: 70.7-96.7%), a specificity of 93.5% (95% CI: 84.9-100%), and an area under the receiver operating characteristic curve of 0.912 (95% CI: 0.835-0.988), indicating excellent discriminatory ability. A user-friendly graphical interface was also developed to facilitate clinical implementation, potentially improving diagnostic efficiency and owner satisfaction.

Bovine alphaherpesvirus 1 (BoHV-1) is the causative agent of infectious bovine rhinotracheitis and reproductive disorders causing significant economic losses in the cattle industry. Both BoHV-1 glycoproteins B (gB) and D (gD) are targets of neutralizing antibodies and desirable antigens for subunit vaccine. In this study, a bivalent subunit vaccine was generated based on the ectodomain of gD and gB expressed by baculoviruses system. Compared with the inactivated vaccine, the bivalent subunit vaccine induced higher neutralizing antibody levels against both the BoHV-1 reference strain and the virulent BoHV-1 field strain. Following intranasally challenge with BoHV-1 J2303, the clinical signs and virus excretion were significantly reduced in rabbits vaccinated with this subunit vaccine whereas severe clinical symptoms appeared in the non-vaccinated rabbits, indicating that the bivalent subunit vaccine provides complete protection against virulent BoHV-1 infection. Considering that the respiratory symptoms caused by J2303 in rabbits is highly similar and even identical to those of cattle, our findings suggest that the bivalent subunit vaccine based on combination of gD with gB protein have promising application to BoHV-1control programs.

Neonatal calf diarrhea caused by Escherichia coli K99 remains a critical challenge in livestock health, yet its precise pathogenic mechanisms are poorly defined. In this study, we identify bile acid (BA) metabolic dysregulation as a key pathogenic mechanism in E. coli K99-induced diarrhea. Using a neonatal calf infection model integrated with multi-omics profiling (including 16S rRNA sequencing, untargeted metabolomics, and targeted bile acid metabolomics), we demonstrate that E. coli K99 infection leads to significant disruption of the gut microbiota, compromises intestinal barrier integrity, and causes region-specific alterations in BA receptor signaling pathways (including FXR, TGR5, RAR, and ABST). Targeted metabolomic analysis revealed the accumulation of toxic primary and secondary BAs, driven by microbial shifts favoring BA-transforming pathogens and depleting BA-sensitive commensals. This microbial dysbiosis-BA imbalance-receptor dysfunction axis provokes immune activation, metabolic disturbances, and epithelial damage. Our study is the first to establish a mechanistic link between E. coli K99 infection and intestinal dysfunction via a microbiota-bile acid-host signaling cascade. These findings uncover a previously unrecognized pathophysiological pathway in bacterial diarrhea and suggest that modulation of gut microbiota and bile acid metabolism represents a promising therapeutic strategy for managing enteric infections in veterinary and potentially human medicine.

Over the last decades, biosecurity has received increasing attention in veterinary medicine and was recently integrated as a competency for One Health field epidemiology framework by international bodies. It is also a standard in the European System of Evaluation of Veterinary Training and in the accreditation of veterinary colleges by the American Veterinary Medical Association Council on Education. To help veterinary students and staff acquire biosecurity skills within veterinary education establishments, we first develop animal biosecurity research, and we spread its results through four interconnected instruments: biosecurity standard operating policies and procedures, a dedicated biosecurity website, an annual biosecurity day, and the production of checklists to assess the biosecurity level of compliance. The use of biosecurity standard operating procedures, the number of visits on the faculty biosecurity website, the number of people trained, and regular biosecurity audits performed are all factors that have contributed to the animal biosecurity to comply with the requirements of the European Association of Establishments for Veterinary Education and by the Council on Outcomes-based Veterinary Education, in the CBVE 2.0 book published by the American Association of Veterinary Medical Colleges. These approaches also contribute to the acquisition and maintenance of the accreditation delivered by the ad hoc bodies. The participation of students in the process allows a better comprehension and appropriation of animal biosecurity.

This study provides a detailed genomic and evolutionary analysis of the heat shock protein (HSP) gene family in the chicken (Gallus gallus), identifying 64 HSP genes. The HSP40 (DNAJ) subfamily was the largest, with 39 members, followed by HSP70, HSP90, and smaller subfamilies. Phylogenetic and structural analyses indicated intricate evolutionary dynamics, encompassing both ancient and recent duplication events. The Ka/Ks ratio suggests that purifying selection is the dominant force, although significant segmental duplications (e.g. DNAJC28/DNAJC30) exhibit evidence of positive selection. Analysis of the protein-protein interaction network identified HSPA8, HSPA9, and HSP90B1 as central hubs. Functional enrichment revealed significant clusters associated with chaperone-mediated protein folding, protein complex assembly, and a novel cluster related to toxin transport. Expression profiling by RT-qPCR revealed notable tissue-specificity, with HSP90 and HSP40 exhibiting the highest upregulation (fold change > 3) in leg muscle relative to liver, highlighting their involvement in musculoskeletal stress adaptation. The findings establish a foundational resource for understanding the molecular mechanisms of stress resilience in poultry, highlighting specific gene families and functional modules as potential targets for enhancing thermotolerance and productivity.

Salmonella enterica subsp. Salmonella Pullorum is a concerned pathogenic microorganism that poses a serious threat to the global poultry industry due to high mortality in chicken. Acquired immunity is considered the most effective means to prevent and control Salmonella pullorum. However, safe and effective vaccines are still lacking worldwide. In this study, Saccharomyces cerevisiae was used as a chassis to design an oral vaccine for pullorum by displaying Salmonella fimbriae and outer membrane proteins on its surface. The results demonstrated that the engineered yeast EY-01 exhibited strong antigenicity as identification and capture by specific antibodies. In addition, oral administration of EY-01 significantly stimulated a 1.4- to 2.7-fold increase in antibody (IgG/A) and immune factors levels (IL-1β/2/4, IFN-γ) in chicks without affecting the growth performance. The ratios of CD4⁺/CD3⁺ and CD8⁺/CD3⁺ T cell subsets in peripheral blood were significantly increased by 2.1-fold. Importantly, 37.5% of chicks were protected from challenge with Salmonella pullorum after oral administration of EY-01. And the Salmonella load in various tissues, especially muscle, was significantly reduced by 7.2%-22.4%. Collectively, EY-01 is a safe and effective oral vaccine to against Salmonella infection in chicks and such surface display-based vaccine is potential to be used for decreasing the poultry diseases.

A heart-convolutional neural network (heart-CNN) was developed and tested for the automatic detection of left atrial enlargement (LAE) from feline thoracic radiographs. A retrospective and multicenter study was performed. Right lateral and dorso-ventral and/or ventro-dorsal thoracic radiographs of cats with concomitant echocardiographic examination were selected from the internal databases of both academic and private referral institutions. Radiographic images were classified as no LAE, mild, moderate and severe LAE, based on echocardiographic reports. Heart-CNN performance was evaluated using confusion matrices and receiver operating characteristic curves for both radiographic projections considering a multiclass and a binary classification. Considering the multiclass classification, for the right lateral view, the area under the curve (AUC) was of 0.73, 0.68, 0.64 and 0.78 for the no LAE, mild, moderate and severe LAE groups, respectively. The AUCs for the dorso-ventral and/or ventro-dorsal images were 0.73, 0.64, 0.63 and 0.76 for the no LAE, mild, moderate and severe LAE groups, respectively. In the binary classification, AUCs were 0.83 and 0.81 for right lateral and dorso-ventral and/or ventro-dorsal projections, respectively. The developed AI-based tool seems to be a promising support for automatic identification of more advanced stages of LAE in cats.

Uterine luminal fluid influences embryonic development and the subsequent phenotype of offspring, yet its detailed metabolomic composition remains poorly characterized. Here, minimally invasive transcervical techniques were employed to collect neat uterine fluid from postpartum dairy cows and cyclic beef cows to allow for metabolomic profiling via targeted mass spectrometry. Objectives were to 1) compare the metabolomic profile of uterine fluid with plasma in dairy cows and 2) assess the impact of dietary rumen-protected methionine and stage of estrous cycle (day 0 vs 7) on plasma and uterine fluid metabolomic profile in beef cows. Results revealed that the concentrations of many metabolites, including amino acids, signaling molecules (e.g. dopamine, gamma-aminobutyric acid) and lipids (e.g. ceramides, diacylglycerols), were higher in uterine fluid than in plasma. An oral bolus of rumen-protected methionine increased uterine concentration of methionine on day 0 of the estrous cycle. The uterine metabolome remained relatively stable between days 0 and 7 although there was temporal variability for a select number of metabolites (cysteine, methionine, methionine sulfoxide, asymmetric dimethylarginine, ceramides, and glycerophospholipids). Correlations between plasma and uterine fluid concentrations were strong or moderate for many amino acids. Collectively, these findings highlight that the uterine lumen is a specialized, selectively regulated biochemical compartment.